SOUTH AMERICAN NEMATOGNATHI. 391 



337, Hisonotus notatus. 



? Otocinclus maculicauda Steindachner, in part. 



Hisonotus nolatus Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. ii, 

 42, 1889 (Santa Cruz; Juiz de Fora). 



Types: No. 7,764. Ninety-five specimens, the largest .04 m. Santa 

 Cruz. Dom Pedro II. 



No. 8,177. One specimen, .043 m. Juiz de Fora. Thayer Expedi- 

 tion. 



Body somewhat depressed anteriorly, wider than deep. 

 Head narrow and comparatively high; occipital end- 

 ing in a triangular process which is bordered by a single 

 nuchal plate; profile rather steep and slightly convex; 

 all the plates of the head strongly hispid; a series of 

 rather large recurved spines margining the granular por- 

 tion of the snout below. 



Orbit 3J in the snout, 7 in the head, 3 in the inter- 

 orbital. 



Outlines of the marginal plate of the snout indistinct. 



Ventral surface entirely covered with about 3 series of 

 irregular plates. 



Lateral plates strongly hispid, the marginal spines 

 scarcely enlarged. 



Distance of dorsal fin from tip of snout little more 

 than 2 in the length; margin of dorsal fin convex. 

 Caudal emarginate. 



Pectoral spine not reaching middle of ventrals, its 

 outer margin spiny. Ventral fins reaching little beyond 

 vent. 



Light brown ; caudal with a large median blackish blotch 

 which extends to the margin of the middle caudal rays; 

 outer caudal rays yellow. 



Head 3; D. I, 7; A. I, 5; V. I, 5; P. I, 6; Lat. 1. 25. 



Dr. Steindachner probably includes minutus with his 

 maculicauda. We here wish to restrict the name macu~ 

 licauda to the species figured by Dr. Steindachner. 



